This study will evaluate the performance and durability of two intraoral fluoride releasing devices with different release rates over a six month period and determine patient acceptance and tolerance of the devices over the same time span. Forty patient volulnteers, aged 11-14 years will be selected as participants and will be divided into 2 groups of 20. The study will consist of a 4 week pretreatment phase, a 26 week treatment phase, and a 4 week posttreatment phase. During the treatment phase, patients, according to their group assignment, will wear a device releasing either 0.05 or 0.10 mg of fluoride per day on their first maxillary molars. Periodically samples of saliva, dental plaque, urine, and serum will be collected to monitor fluoride levels and oral tissues will be monitored for any signs of irritation. Patients will be asked to use a fluoride-containing dentifrice but otherwise will be allowed to follow their normal oral hygiene procedure.